National Electrical Installation Standards

We are being back charged approximately 20k on a project because our team did not properly hang plastic sheeting to catch slurry and runoff over a new electrical panel. My question, does the electrician bear any responsibility for leaving the panel box open with no panel after installation? Is there any code on this? Anyone could have been shocked. We are in Texas. METRO CUTTING
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Hi Charles, at what voltage do you start to need arc flash protection. Brad Lester
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Re: CQD answer published Monday, October 22, 2018 -Receptacle Orientation 1) When I was working as an electrician we wired a house and put the ground down. The lady of the house made us turn them all over. She did not want the receptacles looking at her! Have a good day!! Lowell I. (Laddie) Wolfe Jr. 2) The continuing debate over whether receptacles should be installed grounding prong up or down always amuses me. Both sides seem to forget that nothing in the NEC requires that receptacles be installed vertically. It is perfectly acceptable and often necessary to install receptacles in a horizontal orientation. Don Haskin 3) Ground up or Ground Down. Most union Classed teach Ground up, but there is NO NEC rule about grounding up or down. There are some interesting supporting comments that can be made about the ground post will be first to be hit by a dropping paperclip, in a wire mold the neutral up came point, but no rule. This is a Trick question that is fun to discuss. But it has Merit. Many thanks, Bill Schell
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Can I wire dishwasher and disposal off the 2 appliance counter circuits? Frank Porazzo
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Good day, Has anyone else noticed the requirement to disconnect the grounded conductor from a fuel dispenser has disappeared? The 2017 NEC apparently lost this requirement that has been around for many years. Any insight as to why? I understand this was an effort to match NFPA 30A 6.7 but is it no longer necessary to disconnect the grounded conductor? Thanks. Grant
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Can the flexible cord for a projector connect to a receptacle above a drop ceiling? The ceiling space is not a plenum area. 400.7 (A)(8) & (B) seem to allow it but it's not specific about the appliance being above ceiling. 400.8 (2) & (5) seem to specifically say no. Thanks! Hugh King
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If a basic disconnect has cables terminated inside, but is not terminated at the main. Does this device need to be locked out if it is in the "off" position? This is temporary power in a "green" zone, and the client does not want to lock out the disconnect that feeds motors they are wanting to run intermittently. I told them that if a disconnect is terminated, regardless if it is live, must be locked out. It has to be treated as live correct? They are just using the disconnect basically as a switch rather than a means of on/off. Rob Poston
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We hang three unit heaters there are ten feet in the air where do you put the service switch? We install them on the unit. They want me to put the service switch on the wall down at six feet off the floor and 30 feet from the heater is this right? Bruce Henretty
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I'm an electrician for the government and I been fighting this issue with our building manager and a project manager about multi branch circuits. They have been installed and are used to supply power to nonlinear loads to lighting and also receptacles which feed medical equipment. They have allowed electrical contractors to use 3 ungrounded conductors and one shared neutral from a 4 wire 3 Phase systems using 3 pole type breakers sharing one neutral. Violation of article 410.130(G)(2) none of the neutral conductors have a disconnection means. This was back in 2011, but they still continue to allow this practice, the electrical contractor has stipulated that the installation are in no way in violations to the NEC. So even though 225.33(B), 230.71(B) and 240.15(B), permit two or three single-pole switches or breakers on the multiwire branch circuits that are capable of individual operation—one pole for each ungrounded conductor and one multipole disconnect—provided these devices are equipped with identified handle ties or a master handle to disconnect all ungrounded conductors. Does that mean that’s its ok to use a three pole breakers, with ties, marked in accordance to the code to be use to feed lighting and receptacle circuits that use 3 ungrounded conductors and a share a neutral. Most of the buildings are medical in natural, 3 are dental clinics that do provide surgical care and main building was a hospital but was reduced to clinical services now. Thanks any help to explain if this practice of using a multi branch circuit is still in accordance with new 2017 NEC standards and was this practice allowed back in 2011 Adolfo Munoz
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Orientation of receptacle. Ground up or down? Vito Vacirca Jr
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Article or reference: all of NFPA referring to proper marking of emergency circuits at source and equipment. to include year adapted, volume, and page or article number. J Marranca
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Charlie, Thank you for your service...enjoyable and very informative. Section 300.3(B) discusses conductors of the same circuit and in general, requires that all conductors (including the grounded conductor and all equipment grounding conductors and bonding conductors) to be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord unless otherwise permitted in accordance with 300.3(B)(1) through (B)(4). An exception under 300.3(B)(1) - Parallel Installations - allows conductors that are installed in underground, non-metallic raceways to be arranged as isolated phase installations as long as the raceways are installed in close proximity and comply with 300.20(B). Section 300.5(I) discusses conductors of the same circuit in underground installations. This section also requires all conductors of the same circuit (including the grounded conductor and all equipment grounding conductors) to be installed in the same raceway or cable "or shall be in close proximity in the same trench." Exception No. 2 under this section, however, allows isolated phase, polarity, grounded conductor, and equipment grounding and bonding conductor installations in non-metallic raceways in close proximity where conductors are paralleled as permitted in 310.10(H), and where the conditions of 300.20(B) are met. Now to my question: For an underground 3 phase, 5 wire installation (3 phase conductors, an equipment grounding conductor, and a grounded conductor), can the 3 phase wires and the equipment grounding conductor be installed together in a single underground PVC conduit and the grounded conductor be installed in a separate, adjacent underground PVC conduit? The conductors are "installed in close proximity in the same trench" per the last sentence of Section 300.5(I) and this also appears to meet the general intent covered by Exception No. 2 under Section 300.5(I). However, this is not a parallel installation and each phase is not isolated. All phase conductors (and the equipment grounding conductor) are grouped together in one underground PVC conduit and the grounded conductor (the neutral) is installed in a separate underground PVC conduit with both conduits being side by side (i.e. in close proximity in the same trench). Thanks, Chris DeWeese
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A metal cabinet contains service conductors, their splices, and current transformers (CT), and is located upstream of an 800-amp service disconnecting means. The CT cabinet has only PVC raceways entering and exiting the enclosure, and the engineered drawings do not show any supply-side bonding jumpers in the PVC raceways. Is it correct to assume that this metal CT enclosure must be connected to a supply-side bonding jumper? If so, what is the correct size bonding jumper? Should supply-side bonding jumpers have been included in the drawings? Although NEC Table 250.102 (C)(1) provides sizes of supply-side bonding jumpers, there seems to be no specific text section that references this table for metal enclosures. I have looked at 250.80, 250.92, and 250.102 (C). Can you help me connect the NEC dots to size supply-side bonding jumpers to metal CT enclosures? Curtis Lichty
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Re: CQD answer published Monday, October 8, 2018 -GFCI Protection in Kitchens For the question posted for Friday, October 5, 2018, "Do all circuits in a Kitchen need to GFCI, or only those at the counter top?" Your answer didn't include 210.8(D) Kitchen Dishwasher Branch Circuit. GFCI protection shall be provided for outlets that supply dishwashers installed in dwelling unit locations. To me, since the dishwasher receptacle could be outside of the 6' to sink rule then 210.8(D) makes the use of GFCI protection an absolute. Rich
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Re: CQD answer published Thursday, September 27, 2018 -Tray Cable I have seen TC cable that looks and smells like SO cord. David Green
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